Yeast Phosphoglycerate Mutase: Correlation of Amino Acid Sequence with 0.35 nm (3.5 Å) Resolution X-Ray Crystallographic Structure

1975 ◽  
Vol 3 (6) ◽  
pp. 1092-1092
Author(s):  
LINDA A. FOTHERGILL ◽  
GAIL I. HODGSON ◽  
SUSAN WINN

The complete amino acid sequence of yeast phosphoglycerate mutase comprising 241 residues has been determined. The sequence was deduced from the two cyanogen bromide fragments, and from the peptides derived from these fragments after digestion by a number of proteolytic enzymes. Determination of this sequence now allows a detailed interpretation of the existing high-resolution X-ray crystallographic structure. A comparison of the sequence reported here with the sequences of peptides from phosphoglycerate mutases from other species, and with the sequence of erythrocyte diphosphoglycerate mutase, indicates that these enzymes have a high degree of structural homology. Autolysis of phosphoglycerate mutase by yeast extracts leads to the complete loss of mutase activity, and the formation of electrophoretically distinguishable forms (R. Sasaki, E. Sugimoto & H. Chiba, Archs Biochem. Biophys. 115, 53-61 (1966)). It is apparent from the amino acid sequence that these changes are due to the loss of an 8─12 residue peptide from the C-terminus.


2002 ◽  
Vol 362 (1) ◽  
pp. 131-135 ◽  
Author(s):  
Michael ARAND ◽  
Alexander M. GOLUBEV ◽  
J. R. Brandao NETO ◽  
Igor POLIKARPOV ◽  
R. WATTIEZ ◽  
...  

Extracellular exo-inulinase has been isolated from a solid-phase culture of the filamentous fungus Aspergillus awamori var. 2250. The apparent molecular mass of the monomer enzyme was 69±1kDa, with a pI of 4.4 and a pH optimum of 4.5. The enzyme hydrolysed the β-(2 → 1)-fructan (inulin) and β-(2 → 6)-fructan (levan) via exo-cleavage, releasing fructose. The values for the Michaelis constants Km and Vmax in the hydrolysis of inulin were 0.003±0.0001mM and 175±5μmol·min−1·mg−1. The same parameters in the hydrolysis of levan were 2.08±0.04mg/ml and 1.2±0.02μmol/min per mg, respectively. The gene and cDNA encoding the A. awamori exo-inulinase were cloned and sequenced. The amino acid sequence indicated that the protein belongs to glycoside hydrolase family 32. A surprisingly high similarity was found to fructosyltransferase from Aspergillus foetidus (90.7% on the level of the amino acid sequence), despite the fact that the latter enzyme is unable to hydrolyse inulin and levan. Crystals of the native exo-inulinase were obtained and found to belong to the orthorhombic space group P212121 with cell parameters a = 64.726 Å (1Å = 0.1 nm), b = 82.041 Å and c = 136.075 Å. Crystals diffracted beyond 1.54 Å, and useful X-ray data were collected to a resolution of 1.73 Å.


The positively stained bands of the segment long spacing (s. l. s.) pattern of collagen are shown to be accounted for by the distribution of charged residues in the sequence of the α 1 chain. The native tendon pattern can be constructed by repeated stagger of 234 residues between adjacent molecules, as in the Hodge-Petruska model. The relation of the precise version of this model to negatively stained patterns is shown and the part played by the teleopeptides revealed. A brief discussion of the meridional X-ray reflexions in terms of amino acid sequence is presented and related to electron microscope patterns. Optical diffraction suggests an approximate thirding of the D period. Finally a symmetric structure formed by reconstituting chick cartilage collagen is analysed and its origins revealed as an elaboration of the Hodge-Petruska model. It is shown to be related to the fibrous long spacing (f. l. s. I) structure.


1977 ◽  
Vol 110 (4) ◽  
pp. 643-666 ◽  
Author(s):  
David J.S. Hulmes ◽  
Andrew Miller ◽  
Stephen W. White ◽  
Barbara Brodsky Doyle

1975 ◽  
Vol 3 (6) ◽  
pp. 1058-1058
Author(s):  
LINDA A. FOTHERGILL ◽  
RICHARD N. HARKINS

Functional studies on interferon would be helped by a three-dimensional structure for the molecule. However, it may be several years before the structure of the protein is determined by X-ray crystallography. We have therefore used available methods for predicting the secondary - and the tertiary - structure of a protein from its amino acid sequence to propose a tertiary model involving the packing of four a-helices. Details of this work have been published elsewhere (Sternberg & Cohen 1982).


Sign in / Sign up

Export Citation Format

Share Document